Administration tip for a flexible bag for medical use

ABSTRACT

A perfusion tip for a flexible bag for medical use includes a tube formed in two tubular coaxial parts separated by a transverse pierceable membrane. The tube is provided on its external periphery with an annular projection delimiting an upstream tip portion adapted to be introduced in and fixed to by welding a portion secured to the flexible bag to be equipped, and a downstream tip portion adapted to receive a perfusion line. The tube also includes a ring engaged within the upstream portion and adapted, because of its hardness, to serve as a mandrel during production of the weld between the periphery of the upstream portion and the portion of the bag in which this upstream portion has been introduced, and a cover that caps the downstream portion and is adapted to ensure maintenance of the sterility of the tube while permitting access thereto.

The present invention relates to receptacles with sterile contents and more particularly to flexible bags for medical use and relates to a tip more specifically adapted to perfusion sites such as flexible bags.

Flexible bags for medical use are produced from various materials, particularly from polyolefins such as for example materials of the family of polypropylenes. The invention relates more particularly to flexible bags using polyolefins as the constituent material.

In these flexible bags, the perfusion site is conventionally constituted by a tube of which one portion is held in sandwich fashion between the two surfaces of the sleeve of plastic material from which is produced the flexible bag, the tube being thus welded to the bag in a welding strip that closes the bag.

The tube is separated internally by a thin perforable partition delimiting an upstream chamber permanently in communication with the interior of the bag, and a downstream chamber accessible from the external opening of the tube, which opening is preferably closed by a removable element preserving the sterility of the tube until its use at the site of administration, for example of a perfusion.

Such a device is known and is shown for example in French patent 2 665 633 in the name of the present applicant.

The present invention seeks to improve this type of perfusion site by providing a perfusion type that is more practical, adapted to different structures of communication between the interior and the exterior of flexible bags, particularly of polyolefin, and this under optimum conditions of sealing in line with the junction zone between the tip and the flexible bag thus equipped.

To this end, the invention has for its object a perfusion tip for flexible bags for medical use, of the type comprising a tube formed of two coaxial tubular portions separated by a transverse pierceable membrane, characterized in that said tube is provided on its external periphery with an annular projection, continuous or not, delimiting an upstream tip portion adapted to be introduced and fixed by welding in a portion secured to the flexible bag to be equipped, and a downstream tip portion adapted to receive a perfusion line, and in that it comprises moreover, on the one hand, a ring engaged within said upstream portion and adapted, because of its hardness, to serve as a mandrel during the performance of said welding between the periphery of the upstream portion and the portion of the bag in which this upstream portion has been introduced, and, on the other hand, a cover that caps said downstream portion and is adapted to ensure preservation of the sterility of the tube whilst permitting access to this latter.

Preferably, the tubular end of the downstream portion of the tube has a diameter and a thickness that thins outwardly so as to give to this end resilience during the emplacement of a perfusion line and to ensure good sealing of the trocar of the perfusion line before and after piercing said separating membrane.

The cover capping the downstream portion is moreover preferably constituted by a tubular portion surrounding said downstream portion prolonged by a portion connected to said tubular portion by a region of lesser resistance, that can be broken to give access to the tube of the tip.

The tip according to the invention is adaptable to various types of flexible bags.

Thus it can be directly welded on the bag during its production, the bag inserted in the upstream portion of the tube serving as a rigid mandrel during welding of said upstream portion between the two walls of the sealed sleeve to constitute one of the closure strips of the bag.

The tip can also, in another context, be ensleeved forcibly within an outlet tube forming an integral portion of the flexible bag and welded to this tube with excellent sealing conditions thanks to the presence of said mandrel ring.

Other characteristics and advantages will become apparent from the description which follows, of one embodiment of the device of the invention, which description is given only by way of example and with respect to the accompanying drawings, in which:

FIG. 1 is an axial cross-sectional view of a perfusion tip according to the invention;

FIG. 2 is an axial cross-sectional view of the tube alone;

FIG. 3 is an axial cross-sectional view of the ring alone serving as a mandrel;

FIG. 4 is a an axial cross-sectional view of the cover alone for the tip, and

FIG. 5 shows the assembly of the tip of FIG. 1 with a conventional flexible bag.

The complete tip 1 shown in FIG. 1 comprises a tubular tube 2 capped in part by a cover 3 and provided internally in its portion opposite to that receiving the cover 3, with an annular ring 4.

The tube 2 constitutes the pierceable element of the tip, which is to say it is adapted to be pierced at the time, during use of the flexible bag (not shown) provided with the tip 1, with the help of a trocar (not shown) of a perfusion line.

To this end, the tube 2 is, in known manner, formed by a tubular conduit with a relatively thin wall, provided with a transverse separating membrane 5 substantially in its medial region. By way of example, the membrane 5 has a thickness of the order of several tenths of a millimeter and internally divides the tube into an upstream space 6 in communication with the interior of the flexible bag, and a downstream space 7.

According to one characteristic of the tube 2 of the invention, the portion of this latter delimiting the downstream space 7 has a wall thickness which thins in the direction of the downstream opening 8 of the tube.

The conical profile and reduced thickness of the downstream portion of the tube gives a certain resilience to the end of the tube 2 and ensures good sealing on the trocar of the perfusion line introduced to pierce the membrane 5.

The portion of the tube delimiting the upstream space 6 has a constant wall thickness, for example of the order of one millimeter, the end of the tube, at the height of the opening 8, being by way of comparison of a wall thickness of the order of one-half millimeter.

According to another characteristic of the device of the invention, the tube 2 is provided on its external periphery, substantially in its medial region and facing the upstream space 6 in the embodiment shown in the drawings, with a continuous projection in the form of an annular rib 9 of rectangular cross-section, delimiting in the tube 2 an upstream portion 10 adapted to be introduced into a tubular portion secured to the flexible bag.

This tubular portion can for example be a tubular section 11 (FIG. 5) provided during production of a flexible bag 12, more precisely during forming of the welding strip 13 to close one of the ends of the sleeve of plastic material from which the bag is made.

In FIG. 5, the tube 2 of the tip is shown with its upstream portion 10 completely introduced into said tubular section 11 formed by pressing together the walls of the sleeve about said portion 10. The rib 9 comes into abutment against the end edge of the welded strip 13.

The tip 1 can also be introduced by its portion 10 into an outlet tube of the bag, itself welded to the body of this latter.

The piece 2 is preferably made by molding from a flexible grade of polypropylene for reasons of compatibility with the material of the bags and their tubes.

The downstream portion 14 of the tube 2 is adapted to be capped by the cover 3 which is of generally truncated conical shape with a first portion covering the portion 14 of the tube and prolonged by a portion 15 of reduced diameter, with a thinner wall, the annular connection region 16 between these two portions constituting a zone of lesser resistance that can be broken to give access to the opening 8 of the tube 2.

On the internal surface of the end of the cover 3 opposite the prolongation 15, is provided an internal shoulder 17 adapted to come into abutment against the rib 9 at the end of fitting the cover onto the tube 2.

The cover 3 is preferably made by molding from a rigid frangible grade of polypropylene.

The cover 3 has the object of protecting the portion 14, which is fragile, of the tip, during the phase of sterilization of the bag and of its solution. On the other hand, it maintains the sterility of the tube 2 until its use.

At the time of use of the tip, the projecting portion 15 of the cover is easily broken by bending, at the height of the annular region 16, thereby freeing completely the opening 8.

Finally, the reinforcing ring 4 is a single cylindrical element of constant thickness of the same order as that of the portion 10 of the tube into which it is introduced. The internal end of the ring 4 is however slightly thinned in diameter and in thickness at 18 to facilitate its insertion into the tube 2, whilst the other end is provided with a small peripheral retention projection 19, coming into abutment (FIG. 1) against the end of the tube 2.

The length of the ring 4 corresponds substantially to that of the upstream portion 10 of the tube. The ring 4 is preferably of rigid polypropylene.

It preferably serves as a rigid mandrel when the tip 1 is integrated with a flexible bag in the course of its production (FIG. 5).

Thus, when it is desired to weld a tubular piece on a bag, it is useful to introduce a rigid mandrel within the tubular piece, during the operation of welding, to ensure good welding pressure. On the contrary, in its absence, the tubular portion would collapse and the weld would not be good.

In the case, shown in FIG. 5, of the tip according to the invention, with a tube 2 provided with a membrane 5 which must remain unpierced, it is impossible to introduce a mandrel to obtain good welding between the external surface of the upstream portion 14 of the tip, and the portion of the sleeve surrounding this latter and adapted to form the welding band 13.

According to a very interesting and advantageous characteristic of the device of the invention, it is possible to have a very good weld thanks to the presence of the ring 4 which serves as a rigid mandrel avoiding the collapse of the tube 2 in the course of welding.

Similarly, if the tip 1 is mounted on an outlet tube secured to a flexible bag, a perfect sealing could be achieved by welding the tube to the tip in line with the portion 14 of the tube, the ring 4 then serving, here again, as a rigid mandrel within said portion 14.

Finally, the invention is clearly not limited to the embodiment shown and described above, but on the contrary covers all the modifications, particularly as to the shape and dimensions of the elements 2, 3 and 4 constituting the tip, as well as the material usable for its production. It is to be noted moreover that the rib 9 can be discontinuous or replaced by any other means adapted to the same end of being an abutment both for fitting the cover 3 on the tube 2 and this latter in any tubular receiving element. 

1. Perfusion tip for flexible bags for medical use, of the type comprising a tube (2) formed in two coaxial tubular portions separated by a pierceable transverse membrane (5), characterized in that said tube (2) is provided on is external periphery with an annular projection (9), continuous or not, delimiting an upstream tube portion (10) adapted to be introduced and fixed by welding in a portion secured to the flexible bag to be equipped, and a downstream tip portion (14) adapted to receive a perfusion line, and in that it comprises moreover, on the one hand, a ring (4) engaged within said upstream portion (10) and adapted, because of its hardness, to serve as a mandrel during the execution of said welding between the periphery of the upstream portion and the portion of the bag in which this upstream portion has been introduced, and on the other hand, by a cover (3) that cps said downstream portion (14) and is adapted to ensure the maintenance of sterility of the tube (2) whilst permitting access to this latter.
 2. Perfusion tip according to claim 1, characterized in that the tubular end of the downstream portion (14) of the tube (2) has a diameter and a thickness which decreases outwardly so as to give to this end resilience during emplacement of a perfusion line and to ensure good sealing to the trocar of the perfusion line.
 3. Perfusion tip according to claim 1, characterized in that said cover (3) capping the downstream portion (14) of the tube (2) is constituted by a tubular portion surrounding said downstream portion (14) prolonged by a portion (15) connected to said tubular portion by a region of lesser resistance (16), which can be broken to give access to the tube.
 4. Perfusion tip according to claim 1, characterized in that said ring (4) connected to the interior of said downstream portion (10) of the tube comprises an internal end (18) slightly less in diameter and thickness and an opposite end provided with a retaining projection (19).
 5. Perfusion tip according to claim 1, characterized in that the tube (2), the cover (3) and the ring (4) are made respectively from flexible polypropylene, rigid and frangible polypropylene, and rigid polypropylene. 